Orthogonal line generator

ABSTRACT

An orthogonal line generator is provided which comprises a combination of a straight line generator and a geneva mechanism. The straight line generator is a rotating system of two equal length arms. A first or base arm rotates about one of its ends while a secondary arm pivoted on the other end of the base arm rotates in the opposite direction.

United States Patent Duncan [4 1 Dec. 19, 1972 54] ORTHOGONAL LINEGENERATOR I [72] Inventor: William E. Duncan, China Lake,

Calif.

[73] Assignee: The United States of America as represented by theSecretary of the Navy [22] Filed: March 10, 1971 [21] Appl. No.: 122,952

[52] U.S. Cl..... ..14/s2, 74/436, 14/112 [51] Int.Cl ..Fl6h27/00 [58]FieldofSearch'. ..74/52,436,ll2

[5 6] References Cited UNITED STATES PATENTS 10/1963 Dexter 74/4365/1955 Toby mmml 3,127,777 4/1964 Pietsch 74/52 FOREIGN PATENTS ORAPPLICATIONS 916,740 8/1954 Germany ..74/436 Primary Examiner-MiltonKaufman Assistant Examiner-Wesley S; Ratliff, Jr.

Attarney-R. S. Sciascia, Roy Miller .and Gerald F.

Baker {57] ABSTRACT An orthogonal line generator is provided whichcomprises a combination of a straight line generator and a genevamechanism. The straight line generator is a rotating system of two equallength arms. A first or /base arm rotates about one of its ends while asecondary arm pivoted on the other end of the base arm rotates in theopposite direction.

3 Claims, 4 Drawing Figures PATENTED M01 I91 3.706.235

SHEET 1 OF 3 dIHI/ FIG. I.

I NVENTOR WILLIAM E. DUNCAN BY: ROY MILLER ATTORNEY. GERALD BAKER AGENTPATENTED 19 I973 3.706 235 sum 2 OF 3 FIG. 2.

PATENTED 3.706.235

sum 3 OF 3 FIG. 4.

ORTHOGONAL LINE GENERATOR BACKGROUND OF THE INVENTION In the testing ofgimbal mounted missile seeker devices, for example, it is desirable thatan attractive device be moved within the view of a seeker head undertest to ascertain how well the seeker head follows or tracks movementsof the attractive device. According to the present invention, amechanism is provided which will trace two orthogonal straight lines ina continuously repeated pattern. When a heat source is placed on theapparatus, for example, and a heat seeker head is caused to view theheat source, the seeker head will follow the heat source in itsmovements with a degree of accuracy dependent upon the efficiency of theseeker head.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS DETAILEDDESCRIPTION OF THE INVENTION The device (FIGS. 1 and 2) comprises a basemember 12 supporting a motor 14 which motor drives a gear 18 through areduction gear box 16. Drive gear 18 in turn drives gears 20 and 22.Gear 20 is attached to a shaft 24 which is journaled in the supportmember 12 and passes through a hub 30. A geneva driven gear 26 and asprocket gear 28 are rigidly fastened to opposite ends of hub 30. Theother end of shaft 24 is fastened to one end of first or base arm 32.

Gear 22 is fastened to and drives a shaft 44 which is fastened at itsother end to a geneva drive gear 46 (also see FIG. 4). Geneva drive gear46 has a lock member 48 and a drive pin 50 which operate to drive thegear member 26% revolution for each revolution of gear 46. When gear 26is rotated it causes rotation of sprocket gear 28 through the connectinghub 30, thus driving gear 40 through chain 38. Gear 40 drives shaft 42which is journaled in base arm 32 and fastened to one end of secondaryarm 52.

This latter movement only occurs when one straight line excursion hasbeen completed and a shift is necessary to draw the orthogonal line.When gear 26 is stationary with locking means 48 in place, mountingmeans 60 will move in a straight line beginning at a designated point,proceeding to a limit, returning to the point of origin, proceeding toan opposite limit and returning to the origin.

This movement of mounting means 60 may be more fully understood bytracing the drive when hub remains motionless. Since shaft 24 turnscontinuously, gear will move in a planetary manner around hub 30.Assuming a clockwise motion of shaft 24, Gear 40 will be rotated byreaction with chaim 38 in a counterclockwise direction.

Arms 32 and 52 are equal in length and arm 32 moves with a given angularvelocity in one direction while arm 52 moves with equal velocity in theopposite sense. Therefore since the end about which arm 52 32, the

rotates lS coincident with the free end of arm free end of arm 52, in360 rotation of shaft 24, will trace a straight line from a point oforigin to a point X", returning to the origin thence to a point andagain to the point of origin.

In the embodiment illustrated, pinion 20 has 40 teeth and pinion 22 has50 teeth.

Chain 38 is kept in tension by a gear 56 mounted on a stub shaft 58 onone end of a tension arm 54 which has the other end attached to arm 32through an adjustment slot 57. When motor 14 rotates gears 20 and 22through gear 18, shaft 24 will rotate arm 32 in a continuous manner.Likewise gear 22 will continuously drive gear 46. Rotation of arm 32 byshaft 24 will cause a planetary gear action of the gear 40 when gear28'is in locked condition. When the pin 50 enters a slot 27 on gear 26,gear 26 will start to rotate and gear 40 will be affected therebythrough sprocket 28 and chain drive 38.

In operation, continuous rotation of gear 18 will cause the free end ofarm 52 to describe, with only small deviation, two orthogonal straightlines. When an attractive device is mounted on the mounting means 60 onthe free end of arm 52, the device will be moved in the patterndescribed and will offer an accurately predictable path againstwhich aseeker head path may be checked for investigating tracking accuracy.

What is claimed is:

1. An orthogonal line generator comprising:

a secondary arm and a secondary arm;

said secondary arm being fixed at one end to a first shaft journaled inone end of said base arm;

a driven sprocket gear attached to the other end of said first shaft;

a second shaft attached to the opposite end of said base arm;

a first drive pinion attached to the other end of said second shaft;

a third shaft attached to a second drive pinion in mesh with said firstdrive pinion;

a geneva drive gear attached to the other end of said third shaft;

a hollow shaft journaled on said second shaft;

said hollow shaft having a geneva driven gear fastened on one end andv asprocket drive gear mounted on the other end;

a drive chain connecting said drive sprocket and said driven sprocket;and

tensioning means for said drive chain including an idler sprocketadjustably mounted on said second arm.

2. The apparatus of claim I wherein said geneva mechanism causes onequarter revolution of said sprocket drive gear for every one revolutionof said third shaft.

3. The apparatus of claim 1 wherein said first drive pinion has 40 teethand said second drive pinion has 50 teeth.

Refit-ant No. 3,706,235 I L.

' EDWARD-MJLETCHERQJR.

Attest-ing Officer j j UNITEJ s'aiiTtfa-s' Mim OFFICE;

' Dated December 19, 1972 William E. Danced It is certified that erroreiapears in .the above-identified patent and'that said Letters Patentare hereby corrected as shown below: e I I The second line of claiml((Ioiunm 2, line 34} should read as follows.

I a base amend a secondary arm;

Signed and sealed this 29th day of May 1973 (SEAL) Attest;

- ROBER T' GOTTSCHALK Commissioner of Patents

1. An orthogonal line generator comprising: a secondary arm and asecondary arm; said secondary arm being fixed at one end to a firstshaft journaled in one end of said base arm; a driven sprocket gearattached to the other end of said first shaft; a second shaft attachedto the opposite end of said base arm; a first drive pinion attached tothe other end of said second shaft; a third shaft attached to a seconddrive pinion in mesh with said first drive pinion; a geneva drive gearattached to the other end of said third shaft; a hollow shaft journaledon said second shaft; said hollow shaft having a geneva driven gearfastened on one end and a sprocket drive gear mounted on the other end;a drive chain connecting said drive sprocket and said driven sprocket;and tensioning means for said drive chain including an idler sprocketadjustably mounted on said second arm.
 2. The apparatus of claim 1wherein said geneva mechanism causes one quarter revolution of saidsprocket drive gear for every one revolution of said third shaft.
 3. Theapparatus of claim 1 wherein said first drive pinion has 40 teeth andsaid second drive pinion has 50 teeth.